Is it possible to measure arc length by Measuring Tool?
I would be willing to bet that your Measure dialog box is somewhere off the screen - If you activated the Measure tool, it should be there.
Select the two points and it will show distance at bottom of screen.
If you don't want to trim the rest of the circle, you can use "Split Entities" to break the arc from the circle, you will be able to just measure the arc.
In your case measuring dialog box pops-up. In my case it is not.
Thank you. You are correct. I use two monitors I on 2nd monitor and see dialog box is there.
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